Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
img

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "<!-- AppInternalsXpert BMX Integration Begin -->(.*[\\s\\S]*)<!-- AppInternalsXpert BMX Integration End -->"; final String string = "\n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n\n" + " \n\n" + " \n\n" + " \n" + " \n" + " \n\n" + " \n\n" + " \n\n" + " \n" + " \n\n\n" + " \n" + " \n" + " \n" + " \n" + " \n\n" + " \n" + " \n\n" + " \n\n\n" + " \n" + " \n\n" + " \n" + " \n" + "<script>\n" + "$(function() {\n" + " $( \".tabs\" ).tabs();\n" + " });\n" + "</script>\n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n\n" + " \n\n\n\n\n\n\n\n\n" + " \n" + " \n" + " \n" + " <!-- AppInternalsXpert BMX Integration Begin -->\n" + " <script>\n" + " if(!RVBD_EUE){\n" + " var RVBD_EUE={startJS:Number(new Date()),\n" + " clientId:'',appId:1,\n" + " collector:'apmperformance.correios.com.br',\n" + " collectorHttpPort:80, collectorHttpsPort:443,\n" + " sv:'0401',\n" + " ajax:true, sync:true,\n" + " ajaxResponseTime:true};\n" + " (function(){\n" + " var w=window,l=w.addEventListener,m=w.attachEvent,\n" + " d=document,s='script',t='load',o=RVBD_EUE,\n" + " r=(('https:'===d.location.protocol)?\n" + " 'https://apmperformance.correios.com.br:443':\n" + " 'http://apmperformance.correios.com.br:80')+\n" + " '/jsi/riverbed_appinternals.d.'+\n" + " (o.ajax?'ajax.js':'js'),p=('onpagehide' in w),e=p?'pageshow':t,\n" + " j=d.createElement(s),x=d.getElementsByTagName(s)[0],\n" + " h=function(y){o.ldJS=o.ldJS||new Date();o.per=y?y.persisted:null;},\n" + " i=function(){o.ld=1;};o.cookie=d.cookie;d.cookie=\n" + " '_op_aixPageId=0; path=/; expires='+(new Date(0)).toGMTString();\n" + " o.cookieAfterDelete=d.cookie;j.async=1;j.src=r;\n" + " if(l){l(e,h,false);if(p){l(t,i,false);}}else if(m)\n" + " {m('on'+e,h);if(p){m('on'+t,i);}}\n" + " if(o.sync){d.write('<'+s+' src=\\''+r+'\\'></'+s+'>');}\n" + " else{x.parentNode.insertBefore(j,x);}\n" + " })();}\n" + " </script>\n" + " <script>if(!RVBD_EUE_PARAM){var RVBD_EUE_PARAM={};} RVBD_EUE_PARAM.pageId = 'a2_e6e8c617-d7ec-4acd-a432-08b0febc30e0';</script> \n" + " <!-- AppInternalsXpert BMX Integration End -->\n" + " [cadastrado]\n" + " \n\n" + " \n" + " \n" + " \n" + " "; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html